write F as a sum of an orthogonal and parallel vector

an object is moving in the direction i + j is being acted upon by the force vector 2i + j, express this force as the sum of a force in the direction of motion and a force perpendicular to the direction of motion.

the parallel would be [tex] \hat{i}+\hat{j}[/tex] and the orthogonal would be [tex]\hat{i} – \hat{j}[/tex]